Bone Parenting

The Bone Parenting panel helps you manage and set up root bones for your armature, which is essential for proper model rigging and animation.

What is a Root Bone?

The root bone is the top-level parent bone in your armature hierarchy:

• All other bones are children of the root (directly or indirectly)
• Controls overall model position and rotation
• Essential for proper animation
• Required for VRChat avatars

Why Root Bones Matter

A properly set root bone ensures:

• Correct model behavior in-game
• Proper animation playback
• Correct IK (Inverse Kinematics) behavior
• VRChat compatibility

Root Bone Selection

The panel displays available bones that can serve as the root bone.

Choosing a Root Bone

Typically the root bone is:

• At the center of the model
• Named "Root", "Hips", "Armature", or similar
• The bone that should never move relative to world space
• The parent of the spine/hip bones

Common root bone names:

• Root
• Hips
• Armature
• Hip
• pelvis
• root_bone

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Main Actions

Refresh Root

Updates the root bone list and hierarchy information.

When to use:

• After importing a model
• After making changes to the armature
• After merging armatures
• When bone list seems outdated

How to use:

1. Click Refresh Root
2. Wait for the list to update
3. Review available root bones

Set Root

Establishes the selected bone as the root of the armature.

What it does:

• Reorganizes bone hierarchy
• Sets up proper parenting
• Ensures selected bone is at top level
• Updates armature structure

How to use:

1. Select desired bone from the list
2. Click Set Root
3. Verify hierarchy in Blender's bone view

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Workflow

Setting Up Root Bone (New Model)

1. Import your model
2. Open Bone Parenting panel
3. Click Refresh Root
4. Review available bones
5. Select appropriate root bone
6. Click Set Root
7. Verify hierarchy

Fixing Root Bone Issues

If your model has incorrect root:

1. Identify correct bone (usually Hips or Root)
2. Click Refresh Root
3. Select correct bone
4. Click Set Root
5. Test animations
6. Save changes

After Armature Merging

After using Custom Model Creation:

1. Refresh Root to update hierarchy
2. Check if root is correct
3. Set Root if needed
4. Verify merged bones are properly parented

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Use Cases

Preparing Model for VRChat

1. Import model
2. Fix MMD model (if needed only use on MMD and VRM models)
3. Set proper root bone
4. Configure eye tracking and visemes
5. Export

Fixing Imported Models

Some importers don't set root correctly:

1. Model appears at wrong position
2. Animations don't work correctly
3. Solution: Set proper root bone

After Merging Models

When combining armatures:

1. Merged armature may have confused hierarchy
2. Refresh and Set Root to fix
3. Ensures clean bone structure

Creating Custom Rigs

When building custom rigs:

1. Create bones
2. Set Root at the start
3. Build hierarchy from root
4. Keeps structure organized

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Best Practices

Choosing Root Bone

DO:

• ✅ Choose central, main bone
• ✅ Pick bone at character center
• ✅ Use Hips for humanoid rigs
• ✅ Verify it makes logical sense

DON'T:

• ❌ Choose end-bones (fingers, toes)
• ❌ Select helper bones
• ❌ Pick bones that should move independently
• ❌ Use arbitrary bones

When to Refresh

Refresh Root after:

• Importing models
• Merging armatures
• Adding or deleting bones
• Duplicating armatures
• Major hierarchy changes

After Setting Root

Always verify:

1. Open armature in Edit Mode
2. Check bone hierarchy (shift-click bones to see parents)
3. Verify root bone has no parent
4. Confirm other bones trace back to root
5. Test pose mode to ensure everything moves correctly

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Common Issues

Root Bone List is Empty

Possible causes:

• No armature selected
• Armature has no bones
• Panel needs refresh

Solutions:

• Select your armature object
• Click Refresh Root
• Verify armature has bones

Wrong Bone Appears as Root

Possible causes:

• Hierarchy wasn't updated
• Import issue
• Previous setup incorrect

Solutions:

• Click Refresh Root
• Select correct bone
• Click Set Root
• Verify change took effect

Animations Break After Setting Root

This is rare, but possible:

• Some animations might need rebaking
• Animation constraints may need adjustment
• Usually animations adapt automatically

Solutions:

• Save backup before setting root
• Test animations after change
• If broken, undo and investigate further

Can't Set Root on Specific Bone

Possible causes:

• Bone is locked
• Bone has constraints preventing it
• Armature is in Edit Mode

Solutions:

• Switch to Object or Pose Mode
• Unlock bone if locked
• Remove preventing constraints

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Understanding Bone Hierarchy

How Hierarchies Work

Root ("Armature" for VRC models) (top level)
├── Hips
│   ├── Spine
│   │   ├── Chest
│   │   │   ├── Neck
│   │   │   │   └── Head
│   │   │   ├── Shoulder.L
│   │   │   │   └── Arm.L
│   │   │   └── Shoulder.R
│   │   │       └── Arm.R
│   ├── Leg.L
│   └── Leg.R

• Each bone can have one parent
• Each bone can have multiple children
• Root has no parent

Why Hierarchy Matters

• Animation: Children follow parent rotations
• IK: Bone chains need proper hierarchy
• VRChat: Expects specific hierarchy for avatars
• Export: Unity needs correct bone structure

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Related Pages:

• Custom Model Creation - Merging armatures
• Optimization - Bone merging tools
• Quick Access - Model import/export
• Troubleshooting - Common bone issues